php连接mysql数据库执行sql语句无结果！求搭救

<?php    $host="localhost";    $userName="cheng";    $password="11111111";    $dbName="db_student";    $connID=mysqli_connect($host,$userName,$password);    /*if ($connID){echo "ok";}    else {echo "error";} */    mysqli_select_db($connID,$dbName);    mysqli_query($connID,"set names gbk");        //$query=mysqli_query($connID,"SELECT sno,sname,class,chinese,math,english FROM tb_student");    $result=mysqli_query($connID,"INSERT INTO tb_student(sno, sname, class, chinese, math, english) VALUES ('012531','sbsb','12ji','70','70','70')");    if ($result){echo "ok";}    else die('Error: ' . mysql_error());    mysqli_close($connID);

<?php    $host="localhost";    $userName="cheng";    $password="11111111";    $dbName="db_student";    $connID=mysqli_connect($host,$userName,$password,$dbName);    mysqli_query($connID,"set names gbk");        //$query=mysqli_query($connID,"SELECT sno,sname,class,chinese,math,english FROM tb_student");    $result=mysqli_query($connID,"INSERT INTO tb_student(sno, sname, class, chinese, math, english) VALUES ('012531','sbsb','12ji','70','70','70')");    if ($result){echo "ok";}    else die('Error: ' . mysql_error());    mysqli_close($connID);